Field of the Invention
The present invention relates to, for example, a driving apparatus for driving a mirror unit of an image pickup apparatus such as a single-lens reflex camera.
Description of the Related Art
As a device to drive a mirror unit of a single-lens reflex camera and the like, a device is proposed in which a lever is reciprocally driven by two cam gears meshing with each other. In this proposal, a driving shaft of the lever is supported by a bearing member that is engaged with each of two cam gears such that the driving shaft can be inserted into and drawn out of the bearing member; and the bearing member overlaps the two cam gears, when viewed from the shaft direction in the entire operation range of the lever, so as to prevent the bearing member from dropping out (Japanese Laid-Open Patent Publication (kokai) No. H07-168280). In addition, a technique of introducing a stopper ring mounted as a drop-out stopper of the bearing member onto a construction in which a bearing member rotatably supported by an arm is engaged with a cam, is proposed (Japanese Laid-Open Patent Publication (kokai) No. 2007-327503).
However, in Japanese Laid-Open Patent Publication (kokai) No. H07-168280 mentioned above, when the operation angle of the lever becomes large, it is difficult for the bearing member to overlap the two cam gears in the shaft direction at all times. Accordingly, there is a possibility that the bearing member is caught by a difference in level between the two cam gears and the operation of the lever is thus disturbed.
In the case of the technique in Japanese Laid-Open Patent Publication (kokai) No. 2007-327503 mentioned above, a stopper ring is used as a drop-out stopper of the bearing member, which increases the number of components and the size in the shaft direction.